1. Field of the Invention
The present invention relates to a magnetic bubble memory system, more particularly to a major-minor loop construction magnetic memory system in which access in a single-page mode or a multi-page mode can be selected for each magnetic bubble device in the system.
2. Description of the Prior Art
In general, there are two types of constructions used in magnetic bubble memory systems: single-loop construction and major-minor loop construction. In major-minor loop type magnetic bubble memory systems, there are two access methods: a single-page mode in which single pages are accessed in a minor loop in the magnetic bubble device and a multi-page mode in which two or more pages are accessed in a minor loop in the magnetic bubble device based on one access command.
Magnetic bubble memory systems include one or more magnetic bubble devices, each of which has several bubble storage minor loops. In the prior art magnetic bubble memory systems, however, only one of the above access methods can be used for the devices at one time, i.e., all of the magnetic bubble devices are uniformly accessed in either the single-page or multi-page mode. When a magnetic bubble memory system is set for access in the single-page mode, the response of bubble devices intended for access in the multi-page mode is slow. When the system is set for multi-page mode access, the response of bubble devices intended for single-page mode access is slow. This means the prior art magnetic bubble memory systems cannot provide the optimum overall response.